CODEWITHSUNDEEP
linuxbashsed
Alex
Alex

Reputation: 239

Uncommenting XML tag using sed command on linux environment

On the Linux platform, I need to uncomment this occurrence within an xml file.
I can use the "sed" command to delete the comment on the first occurrence, but then I need to delete the comment also at the end of the tag: </Application-->

I cannot use the "sed" command globally, otherwise, I'll change also others lines commented on in the file.

There is a Linux command to uncomment the tag as per the example below?

              <!-- Application id="MYPROGRAM_BATCH" appl="it.test.apps.batch.MyProgramBatch" logname="BATCH">
                       <Config>
                                       <Active val="xxxxxxxxx"/>
                                       <Interval val="xxxxx"/>
                                       <TemplatePrefix val="xxxxxx" />
                                       <FromAddress val="yyyy" />
                                       <DefaultLang val="yyyyy" />
                       </Config>
              </Application-->

Below is the sed command used to disable the comment on the first occurrence, but I don’t know how to uncomment also on the ninth line. 

sed -i "s/<\!-- Application id=\"MYPROGRAM_BATCH\"/<Application id=\"MYPROGRAM_BATCH\"/g" myFileName.xml

How can I delete the comments also in the </Application--> tag after 9 lines from the first occurrence?

Upvotes: 0

Views: 205

Answers (2)

Pierre Fran&#231;ois
Pierre Fran&#231;ois

Reputation: 6083

This works:

sed -i '/<!-- \(Application id="MYPROGRAM_BATCH"\)/{s//<\1/;n;n;n;n;n;n;n;n;s/-->/>/}' myFileName.xml

It executes a substitution on the opening tag, skips 8 lines and performs the substitution on the closing tag.

This solution is fragile because in case the amount of lines between the opening and closing tag is not exactly 8, the code will be broken.

Anyway, your way to comment lines out by breaking the structure of the XML language is not a good idea: it prevents you from using tools that are more adapted to process XLM files than sed.

If you had commented your lines of code out as follows:

            <!--<Application id="MYPROGRAM_BATCH" appl="it.test.apps.batch.MyProgramBatch" logname="BATCH">
                       <Config>
                                       <Active val="xxxxxxxxx"/>
                                       <Interval val="xxxxx"/>
                                       <TemplatePrefix val="xxxxxx" />
                                       <FromAddress val="yyyy" />
                                       <DefaultLang val="yyyyy" />
                       </Config>
              </Application>-->

you could have used XSLT transformations instead of sed which is not adapted in most cases to process XML files.

Upvotes: 1

Walter A
Walter A

Reputation: 20032

When you are sure about the number of lines, try this (add the -i option when it works)

sed -rz 's%<\!-- Application id="MYPROGRAM_BATCH"(([^\n]*\n){8}[^<]*</Application)-->%<Application id="MYPROGRAM_BATCH"\1>%g' myFileName.xml

Explanation:
sed -rz: Treat newlines as normal characters
s%...%...%: The / is used in the matched string, use another delimiter
(...)-->: Remember everything that matches the inner expressions until -->
([^\n]*\n){8}: Eight times a line including the newline at the end.

Upvotes: 1

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